Disc brakes for trailers and other wheel mounted vehicles typically operate under rugged and demanding conditions, such as in very hot or in very cold environments, over rough terrain, and on steep inclines, all of which require the brakes to be capable of slowing and stopping the trailer on demand. The frequent and prolonged use of brakes tends to generate heat, particularly at the brake pads and rotor where the pads apply friction to the rotor. The heat can be transmitted throughout the other parts of the brake assembly, including to the brake line where the brake fluid is used to operate the brake pads. When the brakes become extremely hot, there is some likelihood that the brake fluid will boil, changing from liquid to a vapor, tending to cause vapor lock in the brake line. This tends to significantly reduce the ability of the brake system to properly apply the brake pads to the brake rotor.
Another problem specifically applies to boat trailers that transport boats to and from launching sites at lakes, oceans, etc. The trailer with a boat mounted thereon is backed into the water, usually with the wheels and brakes of the trailer becoming submerged in the water. Usually this function is performed after the boat has been transported from a storage site to a launch site, which on some occasions may be many miles during which the brakes become hot. When the trailer is backed into the water and the hot brakes are submerged, the colder water tend to rapidly cool the brakes. The rapid cooling of the brakes tends to reduce the internal pressures within the cavities of the brakes, tending to draw water from the lake, etc. into the parts of the brakes. The water accumulated inside the brake tends to reduce the ability of the brake to apply proper force against the rotor to reduce the speed of or stop the rotation of the rotor. Moreover, the presence of water in a brake assembly tends to deteriorate the parts of the brake assembly contacted by the water.
In the past, various solutions have been attempted to avoid overheating of brakes. For example, the rotors of disc brakes have been modified by forming vented rotors, by the placement of a pair of brake rotors in parallel, side-by-side but spaced apart configuration, with connectors positioned between the rotors. This provides two separate surfaces against which the brake pads can operate, and also provides an increased flow of air about all surfaces of the brake rotors by the connectors functioning as a fan that propels air between the rotors. Also, the rotors can be formed with strategically placed holes that do not interfere with the application of the brake pads against the rotor, but which enhance the flow of air through the rotors.
Another overheating prevention approach is to utilized insulation material between the brake pads and the actuator, to limit the amount of heat transfer from the rotor to the pads, from the pads to the brake actuator and the brake fluid within the brake actuator.
While the above noted and other cooling features have been utilized in the past, there is still a need to provide a durable and reliable solution to the problem of overheating brakes, particularly brakes of the type used on vehicles that submerge their wheels in water from time to time.